Sync infra config: HA/Zabbix relocation, Immich storage move, new services

Accumulated uncommitted infra changes:
- Caddyfile: repoint HA/Zabbix to 192.168.1.4/.3, add ~20 new site routes
- Immich: move media to /mnt/smsg, enable CUDA ML, mem limits, rewrite backup.sh
- Add service stacks: agap-mcp, anki, family, freshrss, iperf3, kanboard,
  linkwarden, qbittorrent, radicale, syncthing, vikunja, windows
- openwebui: enable API keys; ollama: drop CPU fallback
- seafile/zabbix: extra_hosts entries; matrix: add user juris
- Remove pihole stack and stale wiki/migrate.py
- Ignore marketplace-mcp (standalone repo) and linkwarden runtime data

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01LeqyaxJF2nbRXJtae2kNB2

syncthing/docker-compose.yml

@@ -0,0 +1,26 @@
+services:
+  syncthing:
+    image: syncthing/syncthing:latest
+    container_name: syncthing
+    hostname: agap
+    restart: unless-stopped
+    volumes:
+      - /mnt/misc/syncthing/config:/var/syncthing/config
+      - /mnt/misc/syncthing/data:/var/syncthing
+    ports:
+      - "127.0.0.1:8384:8384"   # web UI (proxied by Caddy)
+      - "22000:22000/tcp"        # sync protocol TCP
+      - "22000:22000/udp"        # sync protocol UDP
+      - "21027:21027/udp"        # local discovery
+
+  relay:
+    image: syncthing/relaysrv:latest
+    container_name: syncthing-relay
+    restart: unless-stopped
+    env_file: relay.env
+    entrypoint: ["/bin/sh", "-c", "exec /bin/strelaysrv -listen=:22067 -status-srv=:22070 -pools= -token=$$RELAY_TOKEN"]
+    volumes:
+      - /mnt/misc/syncthing/relay-keys:/keys
+    ports:
+      - "22067:22067/tcp"   # relay protocol
+      - "22070:22070/tcp"   # status/metrics

syncthing/relay.env

@@ -0,0 +1 @@
+RELAY_TOKEN=04a4e751b42e1cec36f53ff2a99520d5f6403cdb520f7392